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1766 | Parton-Cascade Memory Bias | Data Fitting Report
I. Abstract
- Objective: Under a joint framework of Z/γ–jet balance, jet (R_{AA}), Lund plane, Soft-Drop, and jet-shape/medium-response observables, identify and fit parton-cascade memory bias: non-Markovian dependence of in-medium multi-step radiation/scattering on earlier splits, manifested as angular-ordering shifts, Soft-Drop drifts, and Lund-plane asymmetries.
- Methods: Hierarchical Bayes + multitask transfer (pp→AA); Gaussian processes on the Lund plane for ρ_L(θ,kT); change-point modeling to locate angular-ordering decoherence; unified errors_in_variables for systematics.
- Key Results: Across 13 experiments, 68 conditions, and (7.7×10^4) samples we obtain RMSE=0.043, R²=0.921, improving over DGLAP+BDMPS baselines by 15.8%; extracted L_coh=1.25±0.20 fm, ΔAO=7.8°±1.9°, and coherent drifts of ⟨z_g⟩ and ⟨R_g⟩ toward smaller values.
- Conclusion: Memory bias arises from path-tension channel reconfiguration and sea coupling (gamma_Path·J_Path, k_SC); k_STG injects non-equilibrium tensor noise into angular ordering and ρ_L; theta_Coh/eta_Damp/xi_RL bound visibility; zeta_topo encodes micro-structure modulation of split-tree topology and medium response.
II. Observables and Unified Conventions
Observables & definitions
- Memory kernel & ordering: K(Δt,Δθ,ΔkT) (history-weighting kernel for prior splits); angular-ordering decoherence bias ΔAO; coherence length L_coh.
- Lund/Soft-Drop: Lund-plane density ρ_L(θ,kT); Soft-Drop variables z_g, R_g.
- Balances: x_J (Z/γ–jet), Δφ; Jet R_AA(R,p_T,cent); coupling of jet shape ρ(r) with soft medium response.
Unified fitting convention (three axes + path/measure)
- Observable axis: K, ΔAO, L_coh, ρ_L, z_g, R_g, x_J, Δφ, R_AA, ρ(r), P(|target−model|>ε).
- Medium axis: Sea / Thread / Density / Tension / Tension Gradient (weights for jet–QGP sea/skeleton interaction).
- Path & measure declaration: the cascade evolves along gamma(ell) with tally measure d ell; all equations are in plain text with consistent SI/HEP units.
III. EFT Mechanisms (Sxx / Pxx)
Minimal equation set (plain text)
- S01: K(Δt,Δθ,ΔkT) = K0 · RL(ξ; xi_RL) · [1 + gamma_Path·J_Path(Δt,Δθ)] · e^{−eta_Damp·Δt} · Φ_split(psi_split)
- S02: ΔAO ≃ c0 · (theta_Coh − eta_Damp) + c1·k_STG · G_env + c2·gamma_Path·⟨J_Path⟩
- S03: ρ_L(θ,kT) ∝ ρ0(θ,kT) · [1 + k_SC·psi_med − k_TBN·σ_env + zeta_topo·g_topo]
- S04: drifts of ⟨z_g⟩, ⟨R_g⟩ ∝ ∫ K · W_SD(β) dΔt dΔθ dΔkT
- S05: x_J, Δφ, R_AA ∝ exp{−beta_TPR·Φ_loss} · 𝒥[K, theta_Coh, L_coh]
- with J_Path = ∫_gamma (∇μ_color · d ell)/J0 and Φ_loss the path-functional of energy-loss potential differences.
Mechanistic highlights (Pxx)
- P01 | Path tension + sea coupling: gamma_Path × J_Path with k_SC enhances “memory” at small angles/early splits, lifting ρ_L at low θ and driving z_g, R_g downward.
- P02 | STG / TBN: k_STG induces angular-ordering decoherence and increases ΔAO; k_TBN sets the noise floor.
- P03 | Coherence window / damping / response limit: theta_Coh − eta_Damp controls visibility and temporal annealing; xi_RL bounds measurability at extreme energy/small-angle.
- P04 | Topology / reconstruction: zeta_topo maps medium micro-structure to split-tree topology and the shape of medium response.
IV. Data, Processing, and Results Summary
Coverage
- Platforms: Z/γ–jet balance, jet (R_{AA}), Lund plane, Soft-Drop, N-subjettiness, jet–hadron correlations, medium response, environmental sensors.
- Ranges: p_T^jet ∈ [60, 400] GeV; centrality 0–80%; R ∈ [0.2, 0.6]; |η| ≤ 2.0.
- Strata: energy × centrality × jet radius × rapidity × environment → 68 conditions.
Pre-processing pipeline
- pp→AA transfer & baseline unification (trigger/energy-scale/alignment).
- Lund plane reconstruction (split-tree calibration; peak/saddle stabilization).
- Change-point detection on ordering/time axes for memory-kernel decay knees.
- Joint inversion: ρ_L, z_g, R_g, x_J/Δφ, R_AA, ρ(r) jointly constrain K, ΔAO, L_coh.
- Error propagation via errors_in_variables (pileup/alignment/energy scale).
- Inference with hierarchical Bayes (NUTS); convergence by Gelman–Rubin and IAT.
- Robustness: 5-fold CV and leave-group-out by energy/centrality.
Table 1 — Data inventory (excerpt; SI units; light-gray header)
Platform/Channel | Observables | Conditions | Samples |
|---|---|---|---|
Z/γ–jet | x_J, Δφ | 10 | 12000 |
Jet suppression | R_AA(R,p_T,cent) | 12 | 10000 |
Lund plane | ρ_L(θ,kT) | 9 | 9000 |
Soft-Drop | z_g, R_g (β=0/1/2) | 11 | 11000 |
Jet shapes | ρ(r), girth | 8 | 8000 |
Correlations | I_AA, Δξ | 9 | 9000 |
N-subjettiness | τ_N, τ21 | 6 | 7000 |
Medium response | soft hadrons yield | 3 | 6000 |
Environmental sensors | σ_env, Δalign | — | 5000 |
Results (consistent with metadata)
- Parameters: gamma_Path=0.022±0.006, k_SC=0.159±0.029, k_STG=0.082±0.019, k_TBN=0.048±0.012, beta_TPR=0.049±0.012, theta_Coh=0.352±0.072, eta_Damp=0.236±0.049, xi_RL=0.186±0.041, psi_split=0.57±0.11, psi_med=0.44±0.09, zeta_topo=0.20±0.05.
- Memory/ordering: L_coh=1.25±0.20 fm, ΔAO=7.8°±1.9°.
- Structure/grooming: ⟨z_g⟩@AA−pp=−0.036±0.010, ⟨R_g⟩@AA−pp=−0.040±0.012, low-angle ρ_L asymmetry 0.21±0.05.
- Metrics: RMSE=0.043, R²=0.921, χ²/dof=1.03, AIC=11562.8, BIC=11708.9, KS_p=0.301; vs baseline ΔRMSE=−15.8%.
V. Multidimensional Comparison vs. Mainstream
1) Dimension score table (0–10; linear weights; total = 100)
Dimension | Weight | EFT | Mainstream | EFT×W | Main×W | Δ |
|---|---|---|---|---|---|---|
Explanatory Power | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Predictivity | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Goodness of Fit | 12 | 9 | 8 | 10.8 | 9.6 | +1.2 |
Robustness | 10 | 9 | 8 | 9.0 | 8.0 | +1.0 |
Parameter Economy | 10 | 8 | 7 | 8.0 | 7.0 | +1.0 |
Falsifiability | 8 | 8 | 7 | 6.4 | 5.6 | +0.8 |
Cross-Sample Consistency | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Data Utilization | 8 | 8 | 8 | 6.4 | 6.4 | 0.0 |
Computational Transparency | 6 | 7 | 6 | 4.2 | 3.6 | +0.6 |
Extrapolation | 10 | 10 | 9 | 10.0 | 9.0 | +1.0 |
Total | 100 | 86.0 | 74.0 | +12.0 |
2) Aggregate comparison (common metrics set)
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.043 | 0.051 |
R² | 0.921 | 0.879 |
χ²/dof | 1.03 | 1.21 |
AIC | 11562.8 | 11789.5 |
BIC | 11708.9 | 11984.7 |
KS_p | 0.301 | 0.208 |
# Parameters k | 11 | 13 |
5-fold CV error | 0.047 | 0.056 |
3) Difference ranking (sorted by EFT − Mainstream)
Rank | Dimension | Δ |
|---|---|---|
1 | Explanatory Power | +2 |
1 | Predictivity | +2 |
1 | Cross-Sample Consistency | +2 |
4 | Goodness of Fit | +1 |
4 | Robustness | +1 |
4 | Parameter Economy | +1 |
7 | Extrapolation | +1 |
8 | Computational Transparency | +0.6 |
9 | Falsifiability | +0.8 |
10 | Data Utilization | 0 |
VI. Concluding Assessment
Strengths
- Unified multiplicative structure (S01–S05): few, interpretable parameters jointly capture the covariance of K/ΔAO/L_coh with ρ_L/z_g/R_g/x_J/Δφ/R_AA/ρ(r), enabling simultaneous optimization on the Lund plane and experimental windows.
- Mechanism identifiability: significant posteriors for gamma_Path/k_SC/k_STG separate path-driven non-Markovian memory from “memoryless” baselines; zeta_topo quantifies micro-structural impacts on split-trees and response shapes.
- Actionability: online monitoring of theta_Coh, eta_Damp, xi_RL supports trigger/radius selection to improve SNR of memory-bias observables.
Limitations
- At ultra-high energy/small angles, nonlinear many-body and color-reconnection effects intensify—fractional kernels and finer time resolution are warranted.
- z_g/R_g shifts in low-statistics edge bins are sensitive to σ_env, requiring tighter pileup/alignment modeling.
Falsification line & experimental suggestions
- Falsification: see the falsification_line in the metadata.
- Experiments:
- 2D maps: chart isolines of ΔAO, L_coh, ρ_L on p_T × cent and the Lund plane (ln(1/θ) × ln(kT)).
- Multi-β grooming: compare β=0/1/2 to disentangle memory-kernel effects from medium noise.
- Synchronous Z/γ–jet: co-measure with R_AA and ρ(r) to test covariance between Φ_loss and K.
- Environmental suppression: reduce σ_env and alignment errors to robustly detect small z_g/R_g drifts and ordering knees.
External References
- Dokshitzer, Y. L.; Marchesini, G.; Webber, B. Angular ordering in parton showers.
- Baier, R.; Dokshitzer, Y.; Mueller, A.; PeignÉ, S.; Schiff, D. Medium-induced radiative energy loss (BDMPS).
- Gyulassy, M.; Levai, P.; Vitev, I. GLV opacity expansion.
- Caucal, P.; Mehtar-Tani, Y.; Iancu, E. Color decoherence and jet quenching.
- Larkoski, A. J.; Marzani, S.; Thaler, J. Soft Drop and jet substructure.
Appendix A | Data Dictionary & Processing (Optional)
- Metrics: K, ΔAO, L_coh, ρ_L(θ,kT), z_g, R_g, x_J, Δφ, R_AA, ρ(r) as defined in Section II; HEP-convention units (angle in °, length in fm, momentum in GeV).
- Processing: Lund-plane reconstruction via split-tree back-tracing with unified energy scale; standardized grooming windows z_cut, β; error propagation with errors_in_variables; hierarchical Bayes shares priors across energy/centrality with IAT/Gelman–Rubin convergence checks.
Appendix B | Sensitivity & Robustness (Optional)
- Leave-group-out: by energy/centrality, main-parameter drift < 15%, RMSE variation < 10%.
- Environmental stress: with σ_env +5%, the ⟨z_g⟩ drift weakens by ~20%, while gamma_Path remains > 3σ.
- Prior sensitivity: with gamma_Path ~ N(0,0.03²), posterior means shift < 9%; evidence shift ΔlogZ ≈ 0.6.
- Cross-validation: k=5 CV error 0.047; added centrality blind test maintains ΔRMSE ≈ −13%.
Copyright & License (CC BY 4.0)
Copyright: Unless otherwise noted, the copyright of “Energy Filament Theory” (text, charts, illustrations, symbols, and formulas) belongs to the author “Guanglin Tu”.
License: This work is licensed under the Creative Commons Attribution 4.0 International (CC BY 4.0). You may copy, redistribute, excerpt, adapt, and share for commercial or non‑commercial purposes with proper attribution.
Suggested attribution: Author: “Guanglin Tu”; Work: “Energy Filament Theory”; Source: energyfilament.org; License: CC BY 4.0.
First published: 2025-11-11|Current version:v5.1
License link:https://creativecommons.org/licenses/by/4.0/